winding numberhttp://plus.maths.org/content/category/tags/winding-number
enWinding numbers: Topography and topology IIhttp://plus.maths.org/content/winding-numbers-topography-and-topology-ii
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Ian Short </div>
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<img class="imagefield imagefield-field_abs_img" width="100" height="100" alt="" src="http://plus.maths.org/content/sites/plus.maths.org/files/abstractpics/5/21_mar_2011_-_1010/icon.jpg?1300702204" /> </div>
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<p>This is the second in a series of two articles in which Ian Short looks at topology using topographical features of maps. Find out about Jordan curves and winding numbers with the help of hermits, lighthouses and drunken sailors.</p>
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<p><em>This is the second in a series of two articles in which we look at topology using topographical features of maps. You may wish to read the <a href="http://plus.maths.org/content/dividing-walls-topology-and-topography-i">first article</a> on dividing walls, although the two articles are largely independent.</em></p>
<h3>The Jordan Curve Theorem</h3>
<p>A hermit hires some builders to construct a wall around his house. The wall they construct is shown in figure 1. Does the wall actually surround the house?</p><p><a href="http://plus.maths.org/content/winding-numbers-topography-and-topology-ii" target="_blank">read more</a></p>http://plus.maths.org/content/winding-numbers-topography-and-topology-ii#commentsjordan curvetopologywinding numberWed, 23 Mar 2011 10:00:00 +0000mf3445449 at http://plus.maths.org/content